Golf ball and mold therefor

Abstract

In a golf ball of the icosahedral dimple arrangement pattern having twenty identical phantom regular triangles projected on its spherical surface, all dimples are arranged within the triangles such that no dimples may intersect the sides of each triangle and a great circle which does not intersect the dimples at all may not be depicted. Some dimples may be arranged at the apexes of each triangle. The golf ball travels a longer distance and provides consistent flight independent of impact points. Also provided is a mold consisting of upper and lower mold cups whose cavity surface is provided with dimple-forming protrusions such that the inventive dimple arrangement may be accomplished. The mold is easy to design and fabricate.

We claim: 
     
       1. In a golf ball of the icosahedral dimple arrangement pattern having twenty identical phantom regular triangles projected on its spherical surface, the improvement wherein the dimples are arranged within the triangles such that no dimple may intersect the sides of each said triangle and a great circle which does not intersect the dimples at all may not be depicted. 
     
     
       2. In a golf ball of the icosahedral dimple arrangement pattern having twenty identical phantom regular triangles projected on its spherical surface, the improvement wherein some dimples are arranged at the apexes of each said triangle and the remaining dimples are arranged within the triangles such that none of said remaining dimples may intersect the sides of each said triangle and a great circle which does not intersect the dimples at all may not be depicted. 
     
     
       3. In a mold for molding a golf ball comprising two mold cups which are mated in a separable manner to define a spherical cavity therebetween, the improvement wherein the mold having twenty identical phantom regular triangles projected on the spherical cavity surface in the icosahedral dimple arrangement pattern is substantially equally divided into two mold cups along the sides of the triangles, and   the cavity surface of each mold cup is provided with dimple-forming protrusions within each said triangle such that no protrusions may intersect the sides of each said triangle and a great circle which does not intersect the protrusions at all may not be depicted when the mold cups are mated.   
     
     
       4. In a mold for molding a golf ball comprising two mold cups which are mated in a separable manner to define a spherical cavity therebetween, the improvement wherein the mold having twenty identical phantom regular triangles projected on the spherical cavity surface in the icosahedral dimple arrangement pattern is substantially equally divided into two along a parting line connecting the sides of the triangles,   the parting line edges of the mold cups at a position corresponding to the apex of the triangle are formed with a notch of a shape corresponding to the planar shape of a dimple,   a pin having an inner end configured into a convex shape capable of forming a dimple is fitted in the notch, and   the cavity surface of each mold cup is provided with dimple-forming protrusions at positions corresponding to the apexes of the triangles except for those on the parting line and within each said triangle such that no protrusions may intersect the sides of each said triangle and a great circle which does not intersect the protrusions at all may not be depicted when the mold cups are mated.